在致命的抗生素压力之前,大肠杆菌细胞是为生存做准备的
Tahmina Hossain1, Abhyudai Singh2, Nicholas C Butzin1,3
1Department of Biology and Microbiology, South Dakota State University , Brookings, South Dakota, USA.
Microbiology spectrum
|September 12, 2023
概括
细菌细胞可以继承非遗传"记忆"以生存抗生素,但这种短暂的状态最终会丢失. 在原始细胞中的这种细胞记忆提供了对致命的抗生素效应的生存优势.
科学领域:
- 微生物学 微生物学
- 遗传学 是一个遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 非遗传因素诱导细胞对细胞的基因表达在同位素细菌群体内的变异性.
- 现型异质性允许细胞的子集,持久细胞,通过进入休眠状态来存活致命的抗生素度.
- 增加抗生素耐药性需要了解细菌生存的机制超越遗传突变.
研究的目的:
- 为了调查细菌持续水平的高变化的来源.
- 为了确定持续水平是否是遗传的非遗传性特征.
- 描述这种遗传性特征的性质和持续时间.
主要方法:
- 修改的卢里亚-德尔布鲁克波动测试使用来自单个细菌细胞的克隆种群.
- 连续稀释和再生长实验,以评估跨代的持续水平稳定性.
- 在安培和阿普拉胺压力下持久水平的比较.
主要成果:
- 在克隆群体中观察到持久水平的显著和一致的变化 (安培的约60-100倍,阿普拉米的约40-70倍).
- 稀释后至少五代 (1:20) 的持久性水平保持稳定,但在进一步稀释和再生长 (>七代,1:100) 后消失.
- 这表明一种短暂的,可再生的细胞记忆,而不是先前存在的基因突变.
结论:
- 存在一个"原始细胞"的子群体,具有暂时的,可遗传的非遗传记忆,赋予抗生素耐受性.
- 这种记忆状态是可重复和可逆的,在丢失之前,可以传承几代人.
- 细菌群体利用这种短暂的细胞记忆来增强抗生素应激的生存能力,而不依赖于遗传变化.
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